[SCSI] qla2xxx: Rework MSI-X handlers.

Since MSI-X vectors do not require a clearing "handshake" from
the system perspective, and the registered handler will not be
called more than once for one occurrence of receipt of a vector,
there is no requirement to flush the risc register write clearing
the interrupt condition in the risc. Also, since the msi-x
registered handlers are optimised for a particular vector, it is
preferable to handle the one vector received per invocation of
the handler.

Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

diff --git a/drivers/scsi/qla2xxx/qla_isr.c b/drivers/scsi/qla2xxx/qla_isr.c
index f61c2fe..c4768c4 100644 (file)
--- a/drivers/scsi/qla2xxx/qla_isr.c
+++ b/drivers/scsi/qla2xxx/qla_isr.c
@@ -1679,7 +1679,6 @@ qla24xx_msix_rsp_q(int irq, void *dev_id)
        qla24xx_process_response_queue(ha);
 
        WRT_REG_DWORD(&reg->hccr, HCCRX_CLR_RISC_INT);
-       RD_REG_DWORD_RELAXED(&reg->hccr);
 
        spin_unlock_irqrestore(&ha->hardware_lock, flags);
 
@@ -1693,7 +1692,6 @@ qla24xx_msix_default(int irq, void *dev_id)
        struct device_reg_24xx __iomem *reg;
        int             status;
        unsigned long   flags;
-       unsigned long   iter;
        uint32_t        stat;
        uint32_t        hccr;
        uint16_t        mb[4];
@@ -1703,7 +1701,7 @@ qla24xx_msix_default(int irq, void *dev_id)
        status = 0;
 
        spin_lock_irqsave(&ha->hardware_lock, flags);
-       for (iter = 50; iter--; ) {
+       do {
                stat = RD_REG_DWORD(&reg->host_status);
                if (stat & HSRX_RISC_PAUSED) {
                        if (pci_channel_offline(ha->pdev))
@@ -1748,8 +1746,7 @@ qla24xx_msix_default(int irq, void *dev_id)
                        break;
                }
                WRT_REG_DWORD(&reg->hccr, HCCRX_CLR_RISC_INT);
-               RD_REG_DWORD_RELAXED(&reg->hccr);
-       }
+       } while (0);
        spin_unlock_irqrestore(&ha->hardware_lock, flags);
 
        if (test_bit(MBX_INTR_WAIT, &ha->mbx_cmd_flags) &&